Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 1318 insertions, 0 deletions

diff --git a/kernel/fs/nfsd/nfsctl.c b/kernel/fs/nfsd/nfsctl.c
new file mode 100644
index 000000000..9690cb4dd
--- /dev/null
+++ b/kernel/fs/nfsd/nfsctl.c
@@ -0,0 +1,1318 @@
+/*
+ * Syscall interface to knfsd.
+ *
+ * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
+ */
+
+#include <linux/slab.h>
+#include <linux/namei.h>
+#include <linux/ctype.h>
+
+#include <linux/sunrpc/svcsock.h>
+#include <linux/lockd/lockd.h>
+#include <linux/sunrpc/addr.h>
+#include <linux/sunrpc/gss_api.h>
+#include <linux/sunrpc/gss_krb5_enctypes.h>
+#include <linux/sunrpc/rpc_pipe_fs.h>
+#include <linux/module.h>
+
+#include "idmap.h"
+#include "nfsd.h"
+#include "cache.h"
+#include "state.h"
+#include "netns.h"
+#include "pnfs.h"
+
+/*
+ *	We have a single directory with several nodes in it.
+ */
+enum {
+	NFSD_Root = 1,
+	NFSD_List,
+	NFSD_Export_features,
+	NFSD_Fh,
+	NFSD_FO_UnlockIP,
+	NFSD_FO_UnlockFS,
+	NFSD_Threads,
+	NFSD_Pool_Threads,
+	NFSD_Pool_Stats,
+	NFSD_Reply_Cache_Stats,
+	NFSD_Versions,
+	NFSD_Ports,
+	NFSD_MaxBlkSize,
+	NFSD_MaxConnections,
+	NFSD_SupportedEnctypes,
+	/*
+	 * The below MUST come last.  Otherwise we leave a hole in nfsd_files[]
+	 * with !CONFIG_NFSD_V4 and simple_fill_super() goes oops
+	 */
+#ifdef CONFIG_NFSD_V4
+	NFSD_Leasetime,
+	NFSD_Gracetime,
+	NFSD_RecoveryDir,
+	NFSD_V4EndGrace,
+#endif
+};
+
+/*
+ * write() for these nodes.
+ */
+static ssize_t write_filehandle(struct file *file, char *buf, size_t size);
+static ssize_t write_unlock_ip(struct file *file, char *buf, size_t size);
+static ssize_t write_unlock_fs(struct file *file, char *buf, size_t size);
+static ssize_t write_threads(struct file *file, char *buf, size_t size);
+static ssize_t write_pool_threads(struct file *file, char *buf, size_t size);
+static ssize_t write_versions(struct file *file, char *buf, size_t size);
+static ssize_t write_ports(struct file *file, char *buf, size_t size);
+static ssize_t write_maxblksize(struct file *file, char *buf, size_t size);
+static ssize_t write_maxconn(struct file *file, char *buf, size_t size);
+#ifdef CONFIG_NFSD_V4
+static ssize_t write_leasetime(struct file *file, char *buf, size_t size);
+static ssize_t write_gracetime(struct file *file, char *buf, size_t size);
+static ssize_t write_recoverydir(struct file *file, char *buf, size_t size);
+static ssize_t write_v4_end_grace(struct file *file, char *buf, size_t size);
+#endif
+
+static ssize_t (*write_op[])(struct file *, char *, size_t) = {
+	[NFSD_Fh] = write_filehandle,
+	[NFSD_FO_UnlockIP] = write_unlock_ip,
+	[NFSD_FO_UnlockFS] = write_unlock_fs,
+	[NFSD_Threads] = write_threads,
+	[NFSD_Pool_Threads] = write_pool_threads,
+	[NFSD_Versions] = write_versions,
+	[NFSD_Ports] = write_ports,
+	[NFSD_MaxBlkSize] = write_maxblksize,
+	[NFSD_MaxConnections] = write_maxconn,
+#ifdef CONFIG_NFSD_V4
+	[NFSD_Leasetime] = write_leasetime,
+	[NFSD_Gracetime] = write_gracetime,
+	[NFSD_RecoveryDir] = write_recoverydir,
+	[NFSD_V4EndGrace] = write_v4_end_grace,
+#endif
+};
+
+static ssize_t nfsctl_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
+{
+	ino_t ino =  file_inode(file)->i_ino;
+	char *data;
+	ssize_t rv;
+
+	if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
+		return -EINVAL;
+
+	data = simple_transaction_get(file, buf, size);
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+
+	rv =  write_op[ino](file, data, size);
+	if (rv >= 0) {
+		simple_transaction_set(file, rv);
+		rv = size;
+	}
+	return rv;
+}
+
+static ssize_t nfsctl_transaction_read(struct file *file, char __user *buf, size_t size, loff_t *pos)
+{
+	if (! file->private_data) {
+		/* An attempt to read a transaction file without writing
+		 * causes a 0-byte write so that the file can return
+		 * state information
+		 */
+		ssize_t rv = nfsctl_transaction_write(file, buf, 0, pos);
+		if (rv < 0)
+			return rv;
+	}
+	return simple_transaction_read(file, buf, size, pos);
+}
+
+static const struct file_operations transaction_ops = {
+	.write		= nfsctl_transaction_write,
+	.read		= nfsctl_transaction_read,
+	.release	= simple_transaction_release,
+	.llseek		= default_llseek,
+};
+
+static int exports_net_open(struct net *net, struct file *file)
+{
+	int err;
+	struct seq_file *seq;
+	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
+
+	err = seq_open(file, &nfs_exports_op);
+	if (err)
+		return err;
+
+	seq = file->private_data;
+	seq->private = nn->svc_export_cache;
+	return 0;
+}
+
+static int exports_proc_open(struct inode *inode, struct file *file)
+{
+	return exports_net_open(current->nsproxy->net_ns, file);
+}
+
+static const struct file_operations exports_proc_operations = {
+	.open		= exports_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= seq_release,
+	.owner		= THIS_MODULE,
+};
+
+static int exports_nfsd_open(struct inode *inode, struct file *file)
+{
+	return exports_net_open(inode->i_sb->s_fs_info, file);
+}
+
+static const struct file_operations exports_nfsd_operations = {
+	.open		= exports_nfsd_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= seq_release,
+	.owner		= THIS_MODULE,
+};
+
+static int export_features_show(struct seq_file *m, void *v)
+{
+	seq_printf(m, "0x%x 0x%x\n", NFSEXP_ALLFLAGS, NFSEXP_SECINFO_FLAGS);
+	return 0;
+}
+
+static int export_features_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, export_features_show, NULL);
+}
+
+static const struct file_operations export_features_operations = {
+	.open		= export_features_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+#if defined(CONFIG_SUNRPC_GSS) || defined(CONFIG_SUNRPC_GSS_MODULE)
+static int supported_enctypes_show(struct seq_file *m, void *v)
+{
+	seq_printf(m, KRB5_SUPPORTED_ENCTYPES);
+	return 0;
+}
+
+static int supported_enctypes_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, supported_enctypes_show, NULL);
+}
+
+static const struct file_operations supported_enctypes_ops = {
+	.open		= supported_enctypes_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+#endif /* CONFIG_SUNRPC_GSS or CONFIG_SUNRPC_GSS_MODULE */
+
+static const struct file_operations pool_stats_operations = {
+	.open		= nfsd_pool_stats_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= nfsd_pool_stats_release,
+	.owner		= THIS_MODULE,
+};
+
+static struct file_operations reply_cache_stats_operations = {
+	.open		= nfsd_reply_cache_stats_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+/*----------------------------------------------------------------------------*/
+/*
+ * payload - write methods
+ */
+
+static inline struct net *netns(struct file *file)
+{
+	return file_inode(file)->i_sb->s_fs_info;
+}
+
+/**
+ * write_unlock_ip - Release all locks used by a client
+ *
+ * Experimental.
+ *
+ * Input:
+ *			buf:	'\n'-terminated C string containing a
+ *				presentation format IP address
+ *			size:	length of C string in @buf
+ * Output:
+ *	On success:	returns zero if all specified locks were released;
+ *			returns one if one or more locks were not released
+ *	On error:	return code is negative errno value
+ */
+static ssize_t write_unlock_ip(struct file *file, char *buf, size_t size)
+{
+	struct sockaddr_storage address;
+	struct sockaddr *sap = (struct sockaddr *)&address;
+	size_t salen = sizeof(address);
+	char *fo_path;
+	struct net *net = netns(file);
+
+	/* sanity check */
+	if (size == 0)
+		return -EINVAL;
+
+	if (buf[size-1] != '\n')
+		return -EINVAL;
+
+	fo_path = buf;
+	if (qword_get(&buf, fo_path, size) < 0)
+		return -EINVAL;
+
+	if (rpc_pton(net, fo_path, size, sap, salen) == 0)
+		return -EINVAL;
+
+	return nlmsvc_unlock_all_by_ip(sap);
+}
+
+/**
+ * write_unlock_fs - Release all locks on a local file system
+ *
+ * Experimental.
+ *
+ * Input:
+ *			buf:	'\n'-terminated C string containing the
+ *				absolute pathname of a local file system
+ *			size:	length of C string in @buf
+ * Output:
+ *	On success:	returns zero if all specified locks were released;
+ *			returns one if one or more locks were not released
+ *	On error:	return code is negative errno value
+ */
+static ssize_t write_unlock_fs(struct file *file, char *buf, size_t size)
+{
+	struct path path;
+	char *fo_path;
+	int error;
+
+	/* sanity check */
+	if (size == 0)
+		return -EINVAL;
+
+	if (buf[size-1] != '\n')
+		return -EINVAL;
+
+	fo_path = buf;
+	if (qword_get(&buf, fo_path, size) < 0)
+		return -EINVAL;
+
+	error = kern_path(fo_path, 0, &path);
+	if (error)
+		return error;
+
+	/*
+	 * XXX: Needs better sanity checking.  Otherwise we could end up
+	 * releasing locks on the wrong file system.
+	 *
+	 * For example:
+	 * 1.  Does the path refer to a directory?
+	 * 2.  Is that directory a mount point, or
+	 * 3.  Is that directory the root of an exported file system?
+	 */
+	error = nlmsvc_unlock_all_by_sb(path.dentry->d_sb);
+
+	path_put(&path);
+	return error;
+}
+
+/**
+ * write_filehandle - Get a variable-length NFS file handle by path
+ *
+ * On input, the buffer contains a '\n'-terminated C string comprised of
+ * three alphanumeric words separated by whitespace.  The string may
+ * contain escape sequences.
+ *
+ * Input:
+ *			buf:
+ *				domain:		client domain name
+ *				path:		export pathname
+ *				maxsize:	numeric maximum size of
+ *						@buf
+ *			size:	length of C string in @buf
+ * Output:
+ *	On success:	passed-in buffer filled with '\n'-terminated C
+ *			string containing a ASCII hex text version
+ *			of the NFS file handle;
+ *			return code is the size in bytes of the string
+ *	On error:	return code is negative errno value
+ */
+static ssize_t write_filehandle(struct file *file, char *buf, size_t size)
+{
+	char *dname, *path;
+	int uninitialized_var(maxsize);
+	char *mesg = buf;
+	int len;
+	struct auth_domain *dom;
+	struct knfsd_fh fh;
+
+	if (size == 0)
+		return -EINVAL;
+
+	if (buf[size-1] != '\n')
+		return -EINVAL;
+	buf[size-1] = 0;
+
+	dname = mesg;
+	len = qword_get(&mesg, dname, size);
+	if (len <= 0)
+		return -EINVAL;
+	
+	path = dname+len+1;
+	len = qword_get(&mesg, path, size);
+	if (len <= 0)
+		return -EINVAL;
+
+	len = get_int(&mesg, &maxsize);
+	if (len)
+		return len;
+
+	if (maxsize < NFS_FHSIZE)
+		return -EINVAL;
+	maxsize = min(maxsize, NFS3_FHSIZE);
+
+	if (qword_get(&mesg, mesg, size)>0)
+		return -EINVAL;
+
+	/* we have all the words, they are in buf.. */
+	dom = unix_domain_find(dname);
+	if (!dom)
+		return -ENOMEM;
+
+	len = exp_rootfh(netns(file), dom, path, &fh,  maxsize);
+	auth_domain_put(dom);
+	if (len)
+		return len;
+	
+	mesg = buf;
+	len = SIMPLE_TRANSACTION_LIMIT;
+	qword_addhex(&mesg, &len, (char*)&fh.fh_base, fh.fh_size);
+	mesg[-1] = '\n';
+	return mesg - buf;	
+}
+
+/**
+ * write_threads - Start NFSD, or report the current number of running threads
+ *
+ * Input:
+ *			buf:		ignored
+ *			size:		zero
+ * Output:
+ *	On success:	passed-in buffer filled with '\n'-terminated C
+ *			string numeric value representing the number of
+ *			running NFSD threads;
+ *			return code is the size in bytes of the string
+ *	On error:	return code is zero
+ *
+ * OR
+ *
+ * Input:
+ *			buf:		C string containing an unsigned
+ *					integer value representing the
+ *					number of NFSD threads to start
+ *			size:		non-zero length of C string in @buf
+ * Output:
+ *	On success:	NFS service is started;
+ *			passed-in buffer filled with '\n'-terminated C
+ *			string numeric value representing the number of
+ *			running NFSD threads;
+ *			return code is the size in bytes of the string
+ *	On error:	return code is zero or a negative errno value
+ */
+static ssize_t write_threads(struct file *file, char *buf, size_t size)
+{
+	char *mesg = buf;
+	int rv;
+	struct net *net = netns(file);
+
+	if (size > 0) {
+		int newthreads;
+		rv = get_int(&mesg, &newthreads);
+		if (rv)
+			return rv;
+		if (newthreads < 0)
+			return -EINVAL;
+		rv = nfsd_svc(newthreads, net);
+		if (rv < 0)
+			return rv;
+	} else
+		rv = nfsd_nrthreads(net);
+
+	return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%d\n", rv);
+}
+
+/**
+ * write_pool_threads - Set or report the current number of threads per pool
+ *
+ * Input:
+ *			buf:		ignored
+ *			size:		zero
+ *
+ * OR
+ *
+ * Input:
+ * 			buf:		C string containing whitespace-
+ * 					separated unsigned integer values
+ *					representing the number of NFSD
+ *					threads to start in each pool
+ *			size:		non-zero length of C string in @buf
+ * Output:
+ *	On success:	passed-in buffer filled with '\n'-terminated C
+ *			string containing integer values representing the
+ *			number of NFSD threads in each pool;
+ *			return code is the size in bytes of the string
+ *	On error:	return code is zero or a negative errno value
+ */
+static ssize_t write_pool_threads(struct file *file, char *buf, size_t size)
+{
+	/* if size > 0, look for an array of number of threads per node
+	 * and apply them  then write out number of threads per node as reply
+	 */
+	char *mesg = buf;
+	int i;
+	int rv;
+	int len;
+	int npools;
+	int *nthreads;
+	struct net *net = netns(file);
+
+	mutex_lock(&nfsd_mutex);
+	npools = nfsd_nrpools(net);
+	if (npools == 0) {
+		/*
+		 * NFS is shut down.  The admin can start it by
+		 * writing to the threads file but NOT the pool_threads
+		 * file, sorry.  Report zero threads.
+		 */
+		mutex_unlock(&nfsd_mutex);
+		strcpy(buf, "0\n");
+		return strlen(buf);
+	}
+
+	nthreads = kcalloc(npools, sizeof(int), GFP_KERNEL);
+	rv = -ENOMEM;
+	if (nthreads == NULL)
+		goto out_free;
+
+	if (size > 0) {
+		for (i = 0; i < npools; i++) {
+			rv = get_int(&mesg, &nthreads[i]);
+			if (rv == -ENOENT)
+				break;		/* fewer numbers than pools */
+			if (rv)
+				goto out_free;	/* syntax error */
+			rv = -EINVAL;
+			if (nthreads[i] < 0)
+				goto out_free;
+		}
+		rv = nfsd_set_nrthreads(i, nthreads, net);
+		if (rv)
+			goto out_free;
+	}
+
+	rv = nfsd_get_nrthreads(npools, nthreads, net);
+	if (rv)
+		goto out_free;
+
+	mesg = buf;
+	size = SIMPLE_TRANSACTION_LIMIT;
+	for (i = 0; i < npools && size > 0; i++) {
+		snprintf(mesg, size, "%d%c", nthreads[i], (i == npools-1 ? '\n' : ' '));
+		len = strlen(mesg);
+		size -= len;
+		mesg += len;
+	}
+	rv = mesg - buf;
+out_free:
+	kfree(nthreads);
+	mutex_unlock(&nfsd_mutex);
+	return rv;
+}
+
+static ssize_t __write_versions(struct file *file, char *buf, size_t size)
+{
+	char *mesg = buf;
+	char *vers, *minorp, sign;
+	int len, num, remaining;
+	unsigned minor;
+	ssize_t tlen = 0;
+	char *sep;
+	struct nfsd_net *nn = net_generic(netns(file), nfsd_net_id);
+
+	if (size>0) {
+		if (nn->nfsd_serv)
+			/* Cannot change versions without updating
+			 * nn->nfsd_serv->sv_xdrsize, and reallocing
+			 * rq_argp and rq_resp
+			 */
+			return -EBUSY;
+		if (buf[size-1] != '\n')
+			return -EINVAL;
+		buf[size-1] = 0;
+
+		vers = mesg;
+		len = qword_get(&mesg, vers, size);
+		if (len <= 0) return -EINVAL;
+		do {
+			sign = *vers;
+			if (sign == '+' || sign == '-')
+				num = simple_strtol((vers+1), &minorp, 0);
+			else
+				num = simple_strtol(vers, &minorp, 0);
+			if (*minorp == '.') {
+				if (num != 4)
+					return -EINVAL;
+				minor = simple_strtoul(minorp+1, NULL, 0);
+				if (minor == 0)
+					return -EINVAL;
+				if (nfsd_minorversion(minor, sign == '-' ?
+						     NFSD_CLEAR : NFSD_SET) < 0)
+					return -EINVAL;
+				goto next;
+			}
+			switch(num) {
+			case 2:
+			case 3:
+			case 4:
+				nfsd_vers(num, sign == '-' ? NFSD_CLEAR : NFSD_SET);
+				break;
+			default:
+				return -EINVAL;
+			}
+		next:
+			vers += len + 1;
+		} while ((len = qword_get(&mesg, vers, size)) > 0);
+		/* If all get turned off, turn them back on, as
+		 * having no versions is BAD
+		 */
+		nfsd_reset_versions();
+	}
+
+	/* Now write current state into reply buffer */
+	len = 0;
+	sep = "";
+	remaining = SIMPLE_TRANSACTION_LIMIT;
+	for (num=2 ; num <= 4 ; num++)
+		if (nfsd_vers(num, NFSD_AVAIL)) {
+			len = snprintf(buf, remaining, "%s%c%d", sep,
+				       nfsd_vers(num, NFSD_TEST)?'+':'-',
+				       num);
+			sep = " ";
+
+			if (len >= remaining)
+				break;
+			remaining -= len;
+			buf += len;
+			tlen += len;
+		}
+	if (nfsd_vers(4, NFSD_AVAIL))
+		for (minor = 1; minor <= NFSD_SUPPORTED_MINOR_VERSION;
+		     minor++) {
+			len = snprintf(buf, remaining, " %c4.%u",
+					(nfsd_vers(4, NFSD_TEST) &&
+					 nfsd_minorversion(minor, NFSD_TEST)) ?
+						'+' : '-',
+					minor);
+
+			if (len >= remaining)
+				break;
+			remaining -= len;
+			buf += len;
+			tlen += len;
+		}
+
+	len = snprintf(buf, remaining, "\n");
+	if (len >= remaining)
+		return -EINVAL;
+	return tlen + len;
+}
+
+/**
+ * write_versions - Set or report the available NFS protocol versions
+ *
+ * Input:
+ *			buf:		ignored
+ *			size:		zero
+ * Output:
+ *	On success:	passed-in buffer filled with '\n'-terminated C
+ *			string containing positive or negative integer
+ *			values representing the current status of each
+ *			protocol version;
+ *			return code is the size in bytes of the string
+ *	On error:	return code is zero or a negative errno value
+ *
+ * OR
+ *
+ * Input:
+ * 			buf:		C string containing whitespace-
+ * 					separated positive or negative
+ * 					integer values representing NFS
+ * 					protocol versions to enable ("+n")
+ * 					or disable ("-n")
+ *			size:		non-zero length of C string in @buf
+ * Output:
+ *	On success:	status of zero or more protocol versions has
+ *			been updated; passed-in buffer filled with
+ *			'\n'-terminated C string containing positive
+ *			or negative integer values representing the
+ *			current status of each protocol version;
+ *			return code is the size in bytes of the string
+ *	On error:	return code is zero or a negative errno value
+ */
+static ssize_t write_versions(struct file *file, char *buf, size_t size)
+{
+	ssize_t rv;
+
+	mutex_lock(&nfsd_mutex);
+	rv = __write_versions(file, buf, size);
+	mutex_unlock(&nfsd_mutex);
+	return rv;
+}
+
+/*
+ * Zero-length write.  Return a list of NFSD's current listener
+ * transports.
+ */
+static ssize_t __write_ports_names(char *buf, struct net *net)
+{
+	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
+
+	if (nn->nfsd_serv == NULL)
+		return 0;
+	return svc_xprt_names(nn->nfsd_serv, buf, SIMPLE_TRANSACTION_LIMIT);
+}
+
+/*
+ * A single 'fd' number was written, in which case it must be for
+ * a socket of a supported family/protocol, and we use it as an
+ * nfsd listener.
+ */
+static ssize_t __write_ports_addfd(char *buf, struct net *net)
+{
+	char *mesg = buf;
+	int fd, err;
+	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
+
+	err = get_int(&mesg, &fd);
+	if (err != 0 || fd < 0)
+		return -EINVAL;
+
+	if (svc_alien_sock(net, fd)) {
+		printk(KERN_ERR "%s: socket net is different to NFSd's one\n", __func__);
+		return -EINVAL;
+	}
+
+	err = nfsd_create_serv(net);
+	if (err != 0)
+		return err;
+
+	err = svc_addsock(nn->nfsd_serv, fd, buf, SIMPLE_TRANSACTION_LIMIT);
+	if (err < 0) {
+		nfsd_destroy(net);
+		return err;
+	}
+
+	/* Decrease the count, but don't shut down the service */
+	nn->nfsd_serv->sv_nrthreads--;
+	return err;
+}
+
+/*
+ * A transport listener is added by writing it's transport name and
+ * a port number.
+ */
+static ssize_t __write_ports_addxprt(char *buf, struct net *net)
+{
+	char transport[16];
+	struct svc_xprt *xprt;
+	int port, err;
+	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
+
+	if (sscanf(buf, "%15s %5u", transport, &port) != 2)
+		return -EINVAL;
+
+	if (port < 1 || port > USHRT_MAX)
+		return -EINVAL;
+
+	err = nfsd_create_serv(net);
+	if (err != 0)
+		return err;
+
+	err = svc_create_xprt(nn->nfsd_serv, transport, net,
+				PF_INET, port, SVC_SOCK_ANONYMOUS);
+	if (err < 0)
+		goto out_err;
+
+	err = svc_create_xprt(nn->nfsd_serv, transport, net,
+				PF_INET6, port, SVC_SOCK_ANONYMOUS);
+	if (err < 0 && err != -EAFNOSUPPORT)
+		goto out_close;
+
+	/* Decrease the count, but don't shut down the service */
+	nn->nfsd_serv->sv_nrthreads--;
+	return 0;
+out_close:
+	xprt = svc_find_xprt(nn->nfsd_serv, transport, net, PF_INET, port);
+	if (xprt != NULL) {
+		svc_close_xprt(xprt);
+		svc_xprt_put(xprt);
+	}
+out_err:
+	nfsd_destroy(net);
+	return err;
+}
+
+static ssize_t __write_ports(struct file *file, char *buf, size_t size,
+			     struct net *net)
+{
+	if (size == 0)
+		return __write_ports_names(buf, net);
+
+	if (isdigit(buf[0]))
+		return __write_ports_addfd(buf, net);
+
+	if (isalpha(buf[0]))
+		return __write_ports_addxprt(buf, net);
+
+	return -EINVAL;
+}
+
+/**
+ * write_ports - Pass a socket file descriptor or transport name to listen on
+ *
+ * Input:
+ *			buf:		ignored
+ *			size:		zero
+ * Output:
+ *	On success:	passed-in buffer filled with a '\n'-terminated C
+ *			string containing a whitespace-separated list of
+ *			named NFSD listeners;
+ *			return code is the size in bytes of the string
+ *	On error:	return code is zero or a negative errno value
+ *
+ * OR
+ *
+ * Input:
+ *			buf:		C string containing an unsigned
+ *					integer value representing a bound
+ *					but unconnected socket that is to be
+ *					used as an NFSD listener; listen(3)
+ *					must be called for a SOCK_STREAM
+ *					socket, otherwise it is ignored
+ *			size:		non-zero length of C string in @buf
+ * Output:
+ *	On success:	NFS service is started;
+ *			passed-in buffer filled with a '\n'-terminated C
+ *			string containing a unique alphanumeric name of
+ *			the listener;
+ *			return code is the size in bytes of the string
+ *	On error:	return code is a negative errno value
+ *
+ * OR
+ *
+ * Input:
+ *			buf:		C string containing a transport
+ *					name and an unsigned integer value
+ *					representing the port to listen on,
+ *					separated by whitespace
+ *			size:		non-zero length of C string in @buf
+ * Output:
+ *	On success:	returns zero; NFS service is started
+ *	On error:	return code is a negative errno value
+ */
+static ssize_t write_ports(struct file *file, char *buf, size_t size)
+{
+	ssize_t rv;
+
+	mutex_lock(&nfsd_mutex);
+	rv = __write_ports(file, buf, size, netns(file));
+	mutex_unlock(&nfsd_mutex);
+	return rv;
+}
+
+
+int nfsd_max_blksize;
+
+/**
+ * write_maxblksize - Set or report the current NFS blksize
+ *
+ * Input:
+ *			buf:		ignored
+ *			size:		zero
+ *
+ * OR
+ *
+ * Input:
+ * 			buf:		C string containing an unsigned
+ * 					integer value representing the new
+ * 					NFS blksize
+ *			size:		non-zero length of C string in @buf
+ * Output:
+ *	On success:	passed-in buffer filled with '\n'-terminated C string
+ *			containing numeric value of the current NFS blksize
+ *			setting;
+ *			return code is the size in bytes of the string
+ *	On error:	return code is zero or a negative errno value
+ */
+static ssize_t write_maxblksize(struct file *file, char *buf, size_t size)
+{
+	char *mesg = buf;
+	struct nfsd_net *nn = net_generic(netns(file), nfsd_net_id);
+
+	if (size > 0) {
+		int bsize;
+		int rv = get_int(&mesg, &bsize);
+		if (rv)
+			return rv;
+		/* force bsize into allowed range and
+		 * required alignment.
+		 */
+		bsize = max_t(int, bsize, 1024);
+		bsize = min_t(int, bsize, NFSSVC_MAXBLKSIZE);
+		bsize &= ~(1024-1);
+		mutex_lock(&nfsd_mutex);
+		if (nn->nfsd_serv) {
+			mutex_unlock(&nfsd_mutex);
+			return -EBUSY;
+		}
+		nfsd_max_blksize = bsize;
+		mutex_unlock(&nfsd_mutex);
+	}
+
+	return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%d\n",
+							nfsd_max_blksize);
+}
+
+/**
+ * write_maxconn - Set or report the current max number of connections
+ *
+ * Input:
+ *			buf:		ignored
+ *			size:		zero
+ * OR
+ *
+ * Input:
+ * 			buf:		C string containing an unsigned
+ * 					integer value representing the new
+ * 					number of max connections
+ *			size:		non-zero length of C string in @buf
+ * Output:
+ *	On success:	passed-in buffer filled with '\n'-terminated C string
+ *			containing numeric value of max_connections setting
+ *			for this net namespace;
+ *			return code is the size in bytes of the string
+ *	On error:	return code is zero or a negative errno value
+ */
+static ssize_t write_maxconn(struct file *file, char *buf, size_t size)
+{
+	char *mesg = buf;
+	struct nfsd_net *nn = net_generic(netns(file), nfsd_net_id);
+	unsigned int maxconn = nn->max_connections;
+
+	if (size > 0) {
+		int rv = get_uint(&mesg, &maxconn);
+
+		if (rv)
+			return rv;
+		nn->max_connections = maxconn;
+	}
+
+	return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%u\n", maxconn);
+}
+
+#ifdef CONFIG_NFSD_V4
+static ssize_t __nfsd4_write_time(struct file *file, char *buf, size_t size,
+				  time_t *time, struct nfsd_net *nn)
+{
+	char *mesg = buf;
+	int rv, i;
+
+	if (size > 0) {
+		if (nn->nfsd_serv)
+			return -EBUSY;
+		rv = get_int(&mesg, &i);
+		if (rv)
+			return rv;
+		/*
+		 * Some sanity checking.  We don't have a reason for
+		 * these particular numbers, but problems with the
+		 * extremes are:
+		 *	- Too short: the briefest network outage may
+		 *	  cause clients to lose all their locks.  Also,
+		 *	  the frequent polling may be wasteful.
+		 *	- Too long: do you really want reboot recovery
+		 *	  to take more than an hour?  Or to make other
+		 *	  clients wait an hour before being able to
+		 *	  revoke a dead client's locks?
+		 */
+		if (i < 10 || i > 3600)
+			return -EINVAL;
+		*time = i;
+	}
+
+	return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%ld\n", *time);
+}
+
+static ssize_t nfsd4_write_time(struct file *file, char *buf, size_t size,
+				time_t *time, struct nfsd_net *nn)
+{
+	ssize_t rv;
+
+	mutex_lock(&nfsd_mutex);
+	rv = __nfsd4_write_time(file, buf, size, time, nn);
+	mutex_unlock(&nfsd_mutex);
+	return rv;
+}
+
+/**
+ * write_leasetime - Set or report the current NFSv4 lease time
+ *
+ * Input:
+ *			buf:		ignored
+ *			size:		zero
+ *
+ * OR
+ *
+ * Input:
+ *			buf:		C string containing an unsigned
+ *					integer value representing the new
+ *					NFSv4 lease expiry time
+ *			size:		non-zero length of C string in @buf
+ * Output:
+ *	On success:	passed-in buffer filled with '\n'-terminated C
+ *			string containing unsigned integer value of the
+ *			current lease expiry time;
+ *			return code is the size in bytes of the string
+ *	On error:	return code is zero or a negative errno value
+ */
+static ssize_t write_leasetime(struct file *file, char *buf, size_t size)
+{
+	struct nfsd_net *nn = net_generic(netns(file), nfsd_net_id);
+	return nfsd4_write_time(file, buf, size, &nn->nfsd4_lease, nn);
+}
+
+/**
+ * write_gracetime - Set or report current NFSv4 grace period time
+ *
+ * As above, but sets the time of the NFSv4 grace period.
+ *
+ * Note this should never be set to less than the *previous*
+ * lease-period time, but we don't try to enforce this.  (In the common
+ * case (a new boot), we don't know what the previous lease time was
+ * anyway.)
+ */
+static ssize_t write_gracetime(struct file *file, char *buf, size_t size)
+{
+	struct nfsd_net *nn = net_generic(netns(file), nfsd_net_id);
+	return nfsd4_write_time(file, buf, size, &nn->nfsd4_grace, nn);
+}
+
+static ssize_t __write_recoverydir(struct file *file, char *buf, size_t size,
+				   struct nfsd_net *nn)
+{
+	char *mesg = buf;
+	char *recdir;
+	int len, status;
+
+	if (size > 0) {
+		if (nn->nfsd_serv)
+			return -EBUSY;
+		if (size > PATH_MAX || buf[size-1] != '\n')
+			return -EINVAL;
+		buf[size-1] = 0;
+
+		recdir = mesg;
+		len = qword_get(&mesg, recdir, size);
+		if (len <= 0)
+			return -EINVAL;
+
+		status = nfs4_reset_recoverydir(recdir);
+		if (status)
+			return status;
+	}
+
+	return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%s\n",
+							nfs4_recoverydir());
+}
+
+/**
+ * write_recoverydir - Set or report the pathname of the recovery directory
+ *
+ * Input:
+ *			buf:		ignored
+ *			size:		zero
+ *
+ * OR
+ *
+ * Input:
+ *			buf:		C string containing the pathname
+ *					of the directory on a local file
+ *					system containing permanent NFSv4
+ *					recovery data
+ *			size:		non-zero length of C string in @buf
+ * Output:
+ *	On success:	passed-in buffer filled with '\n'-terminated C string
+ *			containing the current recovery pathname setting;
+ *			return code is the size in bytes of the string
+ *	On error:	return code is zero or a negative errno value
+ */
+static ssize_t write_recoverydir(struct file *file, char *buf, size_t size)
+{
+	ssize_t rv;
+	struct nfsd_net *nn = net_generic(netns(file), nfsd_net_id);
+
+	mutex_lock(&nfsd_mutex);
+	rv = __write_recoverydir(file, buf, size, nn);
+	mutex_unlock(&nfsd_mutex);
+	return rv;
+}
+
+/**
+ * write_v4_end_grace - release grace period for nfsd's v4.x lock manager
+ *
+ * Input:
+ *			buf:		ignored
+ *			size:		zero
+ * OR
+ *
+ * Input:
+ * 			buf:		any value
+ *			size:		non-zero length of C string in @buf
+ * Output:
+ *			passed-in buffer filled with "Y" or "N" with a newline
+ *			and NULL-terminated C string. This indicates whether
+ *			the grace period has ended in the current net
+ *			namespace. Return code is the size in bytes of the
+ *			string. Writing a string that starts with 'Y', 'y', or
+ *			'1' to the file will end the grace period for nfsd's v4
+ *			lock manager.
+ */
+static ssize_t write_v4_end_grace(struct file *file, char *buf, size_t size)
+{
+	struct nfsd_net *nn = net_generic(netns(file), nfsd_net_id);
+
+	if (size > 0) {
+		switch(buf[0]) {
+		case 'Y':
+		case 'y':
+		case '1':
+			nfsd4_end_grace(nn);
+			break;
+		default:
+			return -EINVAL;
+		}
+	}
+
+	return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%c\n",
+			 nn->grace_ended ? 'Y' : 'N');
+}
+
+#endif
+
+/*----------------------------------------------------------------------------*/
+/*
+ *	populating the filesystem.
+ */
+
+static int nfsd_fill_super(struct super_block * sb, void * data, int silent)
+{
+	static struct tree_descr nfsd_files[] = {
+		[NFSD_List] = {"exports", &exports_nfsd_operations, S_IRUGO},
+		[NFSD_Export_features] = {"export_features",
+					&export_features_operations, S_IRUGO},
+		[NFSD_FO_UnlockIP] = {"unlock_ip",
+					&transaction_ops, S_IWUSR|S_IRUSR},
+		[NFSD_FO_UnlockFS] = {"unlock_filesystem",
+					&transaction_ops, S_IWUSR|S_IRUSR},
+		[NFSD_Fh] = {"filehandle", &transaction_ops, S_IWUSR|S_IRUSR},
+		[NFSD_Threads] = {"threads", &transaction_ops, S_IWUSR|S_IRUSR},
+		[NFSD_Pool_Threads] = {"pool_threads", &transaction_ops, S_IWUSR|S_IRUSR},
+		[NFSD_Pool_Stats] = {"pool_stats", &pool_stats_operations, S_IRUGO},
+		[NFSD_Reply_Cache_Stats] = {"reply_cache_stats", &reply_cache_stats_operations, S_IRUGO},
+		[NFSD_Versions] = {"versions", &transaction_ops, S_IWUSR|S_IRUSR},
+		[NFSD_Ports] = {"portlist", &transaction_ops, S_IWUSR|S_IRUGO},
+		[NFSD_MaxBlkSize] = {"max_block_size", &transaction_ops, S_IWUSR|S_IRUGO},
+		[NFSD_MaxConnections] = {"max_connections", &transaction_ops, S_IWUSR|S_IRUGO},
+#if defined(CONFIG_SUNRPC_GSS) || defined(CONFIG_SUNRPC_GSS_MODULE)
+		[NFSD_SupportedEnctypes] = {"supported_krb5_enctypes", &supported_enctypes_ops, S_IRUGO},
+#endif /* CONFIG_SUNRPC_GSS or CONFIG_SUNRPC_GSS_MODULE */
+#ifdef CONFIG_NFSD_V4
+		[NFSD_Leasetime] = {"nfsv4leasetime", &transaction_ops, S_IWUSR|S_IRUSR},
+		[NFSD_Gracetime] = {"nfsv4gracetime", &transaction_ops, S_IWUSR|S_IRUSR},
+		[NFSD_RecoveryDir] = {"nfsv4recoverydir", &transaction_ops, S_IWUSR|S_IRUSR},
+		[NFSD_V4EndGrace] = {"v4_end_grace", &transaction_ops, S_IWUSR|S_IRUGO},
+#endif
+		/* last one */ {""}
+	};
+	struct net *net = data;
+	int ret;
+
+	ret = simple_fill_super(sb, 0x6e667364, nfsd_files);
+	if (ret)
+		return ret;
+	sb->s_fs_info = get_net(net);
+	return 0;
+}
+
+static struct dentry *nfsd_mount(struct file_system_type *fs_type,
+	int flags, const char *dev_name, void *data)
+{
+	return mount_ns(fs_type, flags, current->nsproxy->net_ns, nfsd_fill_super);
+}
+
+static void nfsd_umount(struct super_block *sb)
+{
+	struct net *net = sb->s_fs_info;
+
+	kill_litter_super(sb);
+	put_net(net);
+}
+
+static struct file_system_type nfsd_fs_type = {
+	.owner		= THIS_MODULE,
+	.name		= "nfsd",
+	.mount		= nfsd_mount,
+	.kill_sb	= nfsd_umount,
+};
+MODULE_ALIAS_FS("nfsd");
+
+#ifdef CONFIG_PROC_FS
+static int create_proc_exports_entry(void)
+{
+	struct proc_dir_entry *entry;
+
+	entry = proc_mkdir("fs/nfs", NULL);
+	if (!entry)
+		return -ENOMEM;
+	entry = proc_create("exports", 0, entry,
+				 &exports_proc_operations);
+	if (!entry) {
+		remove_proc_entry("fs/nfs", NULL);
+		return -ENOMEM;
+	}
+	return 0;
+}
+#else /* CONFIG_PROC_FS */
+static int create_proc_exports_entry(void)
+{
+	return 0;
+}
+#endif
+
+int nfsd_net_id;
+
+static __net_init int nfsd_init_net(struct net *net)
+{
+	int retval;
+	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
+
+	retval = nfsd_export_init(net);
+	if (retval)
+		goto out_export_error;
+	retval = nfsd_idmap_init(net);
+	if (retval)
+		goto out_idmap_error;
+	nn->nfsd4_lease = 90;	/* default lease time */
+	nn->nfsd4_grace = 90;
+	return 0;
+
+out_idmap_error:
+	nfsd_export_shutdown(net);
+out_export_error:
+	return retval;
+}
+
+static __net_exit void nfsd_exit_net(struct net *net)
+{
+	nfsd_idmap_shutdown(net);
+	nfsd_export_shutdown(net);
+}
+
+static struct pernet_operations nfsd_net_ops = {
+	.init = nfsd_init_net,
+	.exit = nfsd_exit_net,
+	.id   = &nfsd_net_id,
+	.size = sizeof(struct nfsd_net),
+};
+
+static int __init init_nfsd(void)
+{
+	int retval;
+	printk(KERN_INFO "Installing knfsd (copyright (C) 1996 okir@monad.swb.de).\n");
+
+	retval = register_pernet_subsys(&nfsd_net_ops);
+	if (retval < 0)
+		return retval;
+	retval = register_cld_notifier();
+	if (retval)
+		goto out_unregister_pernet;
+	retval = nfsd4_init_slabs();
+	if (retval)
+		goto out_unregister_notifier;
+	retval = nfsd4_init_pnfs();
+	if (retval)
+		goto out_free_slabs;
+	retval = nfsd_fault_inject_init(); /* nfsd fault injection controls */
+	if (retval)
+		goto out_exit_pnfs;
+	nfsd_stat_init();	/* Statistics */
+	retval = nfsd_reply_cache_init();
+	if (retval)
+		goto out_free_stat;
+	nfsd_lockd_init();	/* lockd->nfsd callbacks */
+	retval = create_proc_exports_entry();
+	if (retval)
+		goto out_free_lockd;
+	retval = register_filesystem(&nfsd_fs_type);
+	if (retval)
+		goto out_free_all;
+	return 0;
+out_free_all:
+	remove_proc_entry("fs/nfs/exports", NULL);
+	remove_proc_entry("fs/nfs", NULL);
+out_free_lockd:
+	nfsd_lockd_shutdown();
+	nfsd_reply_cache_shutdown();
+out_free_stat:
+	nfsd_stat_shutdown();
+	nfsd_fault_inject_cleanup();
+out_exit_pnfs:
+	nfsd4_exit_pnfs();
+out_free_slabs:
+	nfsd4_free_slabs();
+out_unregister_notifier:
+	unregister_cld_notifier();
+out_unregister_pernet:
+	unregister_pernet_subsys(&nfsd_net_ops);
+	return retval;
+}
+
+static void __exit exit_nfsd(void)
+{
+	nfsd_reply_cache_shutdown();
+	remove_proc_entry("fs/nfs/exports", NULL);
+	remove_proc_entry("fs/nfs", NULL);
+	nfsd_stat_shutdown();
+	nfsd_lockd_shutdown();
+	nfsd4_free_slabs();
+	nfsd4_exit_pnfs();
+	nfsd_fault_inject_cleanup();
+	unregister_filesystem(&nfsd_fs_type);
+	unregister_cld_notifier();
+	unregister_pernet_subsys(&nfsd_net_ops);
+}
+
+MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
+MODULE_LICENSE("GPL");
+module_init(init_nfsd)
+module_exit(exit_nfsd)